看到她微笑换换心情真好。

It's nice to see her smile for a ___change.

“我们在花园吃饭怎么样？”“好啊——换换口味。”

"Shall we eat in the garden?" "Why not - it'll make a ___change."

我们一直开红车——是时候换换了！

We've always had a red car - it's time we had a ___change!